2 dimensional speakers or 3 dimensional speakers

[taters]

I was reading about this on another site but they never fully explained what they were talking about. Does anyone here know the difference and can you explain it to me in layman's terms?

 

[thedudeabides]

Let me try. 2D is width and height. 3D adds depth.

A good analogy is X, Y, and Z coordinates on a typical "grid" mathematical analysis.

 

[rbbert]

Of course one also needs a source that is "3D"...

 

[Duke LeJeune]

I don't know if this is what you're talking about or not, but (at the risk of over-generalizing) I think there may be three different "levels" of speaker dimensionality.

Most decent speakers can give you good left-to-right imaging if they are set up well and if you sit in the right place. Sometimes these images can seem to be beyond the spread of the speakers.

Many speakers, when set up properly, can give you a good sense of depth, placing sound source images in the front-to-back dimension as well as left-to-right within the soundstage. In my opinion this is more enjoyable than mere left-to-right imaging. Sometimes these images and seem to be beyond the walls of the room.

Some speakers can do better still and seemingly take you into the acoustic space that's on the recording. I call this "envelopment", using David Griesinger's term. Achieving envelopment is particularly setup-dependent, in my experience.

All that being said, in my opinion timbre and dynamics matter more. As Jason Serinus wrote many years ago (paraphrasing), "I am not so much interested in where the musicians are on the stage, as I am in why they are on the stage."

 

[dallasjustice]

I think there are different preferences on a continuum when it comes to soundstage dimensions. Some folks like a more focused and precise image. This side of the continuum precisely presents the soundstage front to back, side to side and top to bottom. On the other end of the continuum the soundstage can be much larger and open with a much less precise image. You might find yourself saying that "voice sounds so open but I can't tell where it's coming from."

The term envelopment isn't the best term in this context, although I think I know what it means. The problem is that there are many recordings which have the enveloping soundstage embedded in the recording. So, even if the setup tends to the more precise point on the continuum, it can still reproduce a sense of envelopment.

I believe the more off axis energy at mid and high frequencies the speakers can reproduce, the closer to enveloping end of the spectrum the soundstage may appear.

Having said the foregoing, I've also experienced some speakers setup well which have lots of off axis energy (dipoles) and was able to do do both ends of the continuum at the same time. That's a nice trick but requires a special setup and a big enough room.

 

[Kal Rubinson]

I was reading about this on another site but they never fully explained what they were talking about. Does anyone here know the difference and can you explain it to me in layman's terms?

Too bad that they do not define the terms because, afaik, there is no standard for those terms as applied to loudspeakers, as opposed to arrays of loudspeakers.

 

[Fitzcaraldo215]

Let me try. 2D is width and height. 3D adds depth.

A good analogy is X, Y, and Z coordinates on a typical "grid" mathematical analysis.

I do not know where the OP's vague statement came from. But, correctly, yes, it is x,y, z. Mono is zero dimensional (one point), 2-channel stereo is one dimensional (a line between the 2 speakers), and 5/7.1 Mch are 2 dimensional (a plane defined by the speaker array). 3D adds a height dimension using additional height speakers (Atmos, Auro, etc). However, all these speaker geometries can be perceptually enhanced in the depth dimension via phantom imaging, much like a 2D painting can suggest depth by using geometric and atmospheric perspective. So, mono, stereo or Mch can suggest depth via phantom imaging.

To my mind, there is no such thing as a 2D or 3D speaker. The geometric array and number of speakers determines whether it is 0,1,2, or 3D. Phantom imaging is a given in all cases to add perceptual depth. And, some speakers in certain room/system setups may do this better than others, but there is usually more involved than just the speakers themselves.

 

[DaveC]

I don't know if this is what you're talking about or not, but (at the risk of over-generalizing) I think there may be three different "levels" of speaker dimensionality.

Most decent speakers can give you good left-to-right imaging if they are set up well and if you sit in the right place. Sometimes these images can seem to be beyond the spread of the speakers.

Many speakers, when set up properly, can give you a good sense of depth, placing sound source images in the front-to-back dimension as well as left-to-right within the soundstage. In my opinion this is more enjoyable than mere left-to-right imaging. Sometimes these images and seem to be beyond the walls of the room.

Some speakers can do better still and seemingly take you into the acoustic space that's on the recording. I call this "envelopment", using David Griesinger's term. Achieving envelopment is particularly setup-dependent, in my experience.

All that being said, in my opinion timbre and dynamics matter more. As Jason Serinus wrote many years ago (paraphrasing), "I am not so much interested in where the musicians are on the stage, as I am in why they are on the stage."

Good post, I agree... IMO a speaker/system that can't create an immersive/enveloping soundstage has problems as other kinds of details will be obscured too, not just the spatial information on the recording. Setup is key, even moreso with conventional wide-dispersion speakers while controlled directivity speakers can accomplish this in a relatively untreated room. I also agree timbre and dynamics are important... not sure about more important as I want it all!

 

[DaveC]

I think there are different preferences on a continuum when it comes to soundstage dimensions. Some folks like a more focused and precise image. This side of the continuum precisely presents the soundstage front to back, side to side and top to bottom. On the other end of the continuum the soundstage can be much larger and open with a much less precise image. You might find yourself saying that "voice sounds so open but I can't tell where it's coming from."

The term envelopment isn't the best term in this context, although I think I know what it means. The problem is that there are many recordings which have the enveloping soundstage embedded in the recording. So, even if the setup tends to the more precise point on the continuum, it can still reproduce a sense of envelopment.

I believe the more off axis energy at mid and high frequencies the speakers can reproduce, the closer to enveloping end of the spectrum the soundstage may appear.

Having said the foregoing, I've also experienced some speakers setup well which have lots of off axis energy (dipoles) and was able to do do both ends of the continuum at the same time. That's a nice trick but requires a special setup and a big enough room.

It's actually the other way 'round as wide-dispersion speakers create far more time-delayed reflections that obscure fine detail and spatial information, making setup/acoustics of the room ultra-important. A point source with controlled directivity is the ultimate in creating an enveloping soundstage and it can be accomplished in a relatively untreated room as first reflections are eliminated. I've heard precious few standard cone/dome speaker systems create a soundstage that's competitive with CD speakers.

Dipoles can have some of the narrowest dispersion patterns of any speaker type, as off-axis sound is canceled by the dipole arrangement. Speaker systems like Sanders can provide an enveloping soundstage but imo the dispersion is too narrow, creating too much difference in sound from small movements of your head, making for a "head-in-vice" listening experience.